#!/usr/bin/env python3
import hashlib
import json
import os
import pathlib
import sys
import tempfile

import bpy


def report(task, modifier_type, object_name):
    obj = bpy.data.objects.get(object_name)
    if obj is None:
        raise RuntimeError(f"{object_name} is missing")
    modifiers = [modifier for modifier in obj.modifiers if modifier.type == modifier_type]
    if len(modifiers) != 1:
        raise RuntimeError(f"expected one {modifier_type} modifier, found {len(modifiers)}")
    modifier = modifiers[0]
    value = {
        "task": task,
        "objectId": "object:" + obj.name,
        "modifier": {
            "name": modifier.name,
            "type": modifier.type,
            "typeCode": bpy.types.Modifier.bl_rna.properties["type"].enum_items[modifier.type].value,
            "showViewport": bool(modifier.show_viewport),
            "showRender": bool(modifier.show_render),
            "showEditMode": bool(modifier.show_in_editmode),
            "showOnCage": bool(modifier.show_on_cage),
        },
    }
    if obj.type == "MESH":
        value["meshId"] = "mesh:" + obj.data.name
    if modifier_type == "DECIMATE":
        value["modifier"]["ratio"] = float(modifier.ratio)
        value["modifier"]["iterations"] = int(modifier.iterations)
        value["modifier"]["angleLimit"] = float(modifier.angle_limit)
        value["modifier"]["decimateType"] = modifier.decimate_type
        value["modifier"]["decimateMode"] = {"COLLAPSE": 0, "DISSOLVE": 1, "UNSUBDIV": 2}[modifier.decimate_type]
    if modifier_type == "DISPLACE":
        value["modifier"]["direction"] = {"X": 0, "Y": 1, "Z": 2, "NORMAL": 3, "CUSTOM_NORMAL": 4}[modifier.direction]
        value["modifier"]["strength"] = float(modifier.strength)
        value["modifier"]["midLevel"] = float(modifier.mid_level)
        value["modifier"]["space"] = {"GLOBAL": 0, "LOCAL": 1, "NORMAL": 2}.get(modifier.texture_coords, 0)
        value["modifier"]["textureMapping"] = {"GLOBAL": 1, "LOCAL": 2, "OBJECT": 3, "UV": 4}.get(modifier.texture_coords, 1)
    if modifier_type == "EDGE_SPLIT":
        value["modifier"]["splitAngle"] = float(modifier.split_angle)
    if modifier_type == "SMOOTH":
        value["modifier"]["factor"] = float(modifier.factor)
        value["modifier"]["iterations"] = int(modifier.iterations)
        value["modifier"]["vertexGroup"] = modifier.vertex_group
        value["modifier"]["smoothFlags"] = (
            (1 if modifier.invert_vertex_group else 0)
            | (2 if modifier.use_x else 0)
            | (4 if modifier.use_y else 0)
            | (8 if modifier.use_z else 0)
        )
    return value


def main():
    arguments = sys.argv[sys.argv.index("--") + 1 :]
    if len(arguments) != 5:
        raise SystemExit("usage: blender -b --python check-generic-modifier-desktop.py -- FIXTURE REPORT TASK TYPE OBJECT")
    fixture = pathlib.Path(arguments[0]).resolve()
    output = pathlib.Path(arguments[1]).resolve()
    task, modifier_type, object_name = arguments[2:]
    bpy.ops.wm.open_mainfile(filepath=str(fixture), load_ui=False)
    before = report(task, modifier_type, object_name)
    descriptor, temporary = tempfile.mkstemp(prefix="m16-generic-modifier-reopen-", suffix=".blend", dir=fixture.parent)
    os.close(descriptor)
    try:
        bpy.ops.wm.save_as_mainfile(filepath=temporary, check_existing=False, compress=True)
        bpy.ops.wm.open_mainfile(filepath=temporary, load_ui=False)
        after = report(task, modifier_type, object_name)
    finally:
        pathlib.Path(temporary).unlink(missing_ok=True)
    if before != after:
        raise RuntimeError(f"modifier save/reopen drift: {before} != {after}")
    value = {"schemaVersion": 1, "task": task, "operation": modifier_type + "_MODIFIER_DESKTOP", "fixture": str(fixture), "fixtureSha256": hashlib.sha256(fixture.read_bytes()).hexdigest(), "modifier": after, "saveReopen": "EXACT", "blenderVersion": bpy.app.version_string}
    output.parent.mkdir(parents=True, exist_ok=True)
    output.write_text(json.dumps(value, indent=2, sort_keys=True) + "\n", encoding="utf-8")
    print(f"generic-modifier-desktop-ok task={task} type={modifier_type} mesh={after['meshId']} saveReopen=exact")


if __name__ == "__main__":
    main()